--  @testpoint:opengauss关键字preceding(非保留)，作为函数名

--关键字不带引号-成功
drop function if exists preceding;
create function preceding(i integer)
returns integer
as $$
begin
    return i+1;
end;
$$ language plpgsql;
/
drop function preceding;
--关键字带双引号-成功
drop function if exists "preceding";
create function "preceding"(i integer)
returns integer
as $$
begin
    return i+1;
end;
$$ language plpgsql;
/
drop function "preceding";
--关键字带单引号-合理报错
drop function if exists 'preceding';
create function 'preceding'(i integer)
returns integer
as $$
begin
    return i+1;
end;
$$ language plpgsql;
/
--关键字带反引号-合理报错
drop function if exists `preceding`;
create function `preceding`(i integer)
returns integer
as $$
begin
    return i+1;
end;
$$ language plpgsql;
/